Early attempts, using portable systems to abrade installed bathtubs to render them slip resistant, have met with limited success. These machines cause a stream of fine abrasive particles to be impinged at high velocity against a stenciled rubber template placed in the bottom of the tub. This template defines the pattern to be etched on the bottom of the tub.
Previous machines have lacked the features to automatically maintain the abrading particle stream normal to and in proper registration with the selected areas to be abraded. These machines also lacked the capability to produce an infinitely varied abraded pattern.
Accordingly, a portable, automatic abrading machine is needed which will provide the capabilities lacking in the earlier machines.